A known seat slide apparatus for a vehicle is disclosed in JP2008-247143A (which will be hereinafter referred to as Reference 1), for example. The seat slide apparatus disclosed in Reference 1 includes a lower rail fixed to a vehicle floor and an upper rail fixed to a vehicle seat and supported by the lower rail so as to be movable relative to the lower rail. The seat slide apparatus also includes a lock member that restricts a relative movement between the lower rail and the upper rail. The restriction of the relative movement between the lower rail and the upper rail by the lock member (i.e., a locked state of the lock member) is released, for example, by an operation of an operation handle by an occupant seated on the aforementioned vehicle seat.
The seat slide apparatus disclosed in Reference 1 also includes a memory member 93 movably supported within an inner void having a box shape and formed between a lower rail 91 and an upper rail 92 in a longitudinal direction of the lower rail 91. The memory member 93 is prevented from moving by engaging with the lower rail 91. Further, the seat slide apparatus includes a receiving potion 94 and a memory plate 95. The receiving portion 94 and the memory plate 95 are fixed to the upper rail 92 so as to hold the memory member 93 to integrally move with the upper rail 92 in a state where a restriction of the relative movement between the lower rail 91 and the upper rail 92 by the lock member is released during a normal slide operation. Specifically, in the normal slide operation, the occupant seated on the vehicle seat, for example, releases the lock member (as a result, the lock member is brought to an unlocked state to thereby permit the relative movement between the lower rail and the upper rail) on a basis of an operation of an operation handle so as to adjust the position of the vehicle seat. The receiving portion 94 and the memory plate 95 also hold the memory member 93 so that the engagement of the memory member 93 with the lower rail 91 is maintained in the unlocked state of the lock member in association with a forward folding operation of a seat back of the vehicle seat. Therefore, at a time of a walk-in operation where the a passenger gets in or out of a rear seat in the rear of the vehicle seat, for example, the movement of the upper rail 92 (i.e., the vehicle seat) is permitted while the engagement between the memory member 93 and the lower rail 91 is maintained by a pressing portion 95a of the memory plate 95. After the passenger gets in or out of the rear seat, the upper rail 92 (i.e., the vehicle seat) is moved to an original position (a memory position) where the engagement between the memory member 93 and the lower rail 91 by the pressing portion 95a of the memory plate 95 is releasable and thereafter the seat back is pulled up from the forwardly folded state. As a result, the lock member is again brought to the locked state at the original position where the movement of the upper rail is restricted.
According to Reference 1, in a case where the memory member 93 integrally moves with the upper rail 92, the memory member 93 is held while being sandwiched by a rear end portion of the receiving portion 94 and a front holding portion 95b of the memory plate 95. Thus, a position where the memory member 93 is held (i.e., a holding position thereof) may vary on a basis of an accumulation of a production variation of each of the receiving portion 94 and the memory plate 95 (the front holding portion 95b), an assembly variation thereof, and the like. As a result, the memory member 93 may be loose and an operation of the memory member 93 when the memory member 93 engages with the lower rail 91 may be unstable.
That is, as illustrated in FIG. 15, in a case where the holding position of the memory member 93 varies significantly, positions of an engagement bore 91a formed at the lower rail 91 and a memory pin 93a of the memory member 93 may not match in the longitudinal direction or a height direction of the lower rail 91, which leads to the aforementioned unstable operation of the memory member 93.
A need thus exists for a seat slide apparatus for a vehicle which is not susceptible to the drawback mentioned above.